Developments in biotechnology have made it possible to produce a large variety of monoclonal antibodies for pharmaceutical applications. Because antibodies are larger and more complex than traditional organic and inorganic drugs, the formulation of such proteins poses special problems. One of the problems is the elevated viscosity values of antibody formulations, especially at high protein concentrations. Another problem is maintaining stability in antibody formulations, which is a critical concern for regulatory agencies. The delivery of high protein concentration is often required for subcutaneous administration due to volume limitations and dose requirements. Subcutaneous administration is an attractive route of delivery because it is less invasive for patients and reduces inconvenience and discomfort for them. Proteins tend to form viscous solutions at high concentration because of their macromolecular nature and potential for intermolecular interactions. Therefore, there is a need to develop stable antibody formulations as well as highly concentrated antibody formulations with viscosities at levels that facilitate the manufacture, preparation and administration of the antibody.